It is senseless to configure the ipv6-dhcp hook
multiple times for a zone.

Signed-off-by: Jonatan Schlag <jonatan.schlag(a)ipfire.org>
---
 src/hooks/configs/ipv6-dhcp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/hooks/configs/ipv6-dhcp b/src/hooks/configs/ipv6-dhcp
index 03dbbf0..74ec765 100644
--- a/src/hooks/configs/ipv6-dhcp
+++ b/src/hooks/configs/ipv6-dhcp
@@ -27,6 +27,11 @@ hook_new() {
 	local zone="${1}"
 	shift
 
+	if zone_config_hook_is_configured ${zone} "ipv6-dhcp"; then
+		log ERROR "You can configure the ipv6-dhcp hook only once for a zone"
+		return ${EXIT_ERROR}
+	fi
+
 	zone_config_settings_write "${zone}" "${HOOK}"
 
 	exit ${EXIT_OK}
-- 
2.6.3